@article{WehnerRoehrStepanenkoetal.2020,
  author    = {Wehner, Marius and R{\"o}hr, Merle Insa Silja and Stepanenko, Vladimir and W{\"u}rthner, Frank},
  title     = {Control of self-assembly pathways toward conglomerate and racemic supramolecular polymers},
  series = {Nature Communications},
  volume    = {11},
  journal   = {Nature Communications},
  doi       = {10.1038/s41467-020-19189-8},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230580},
  year      = {2020},
  abstract  = {Homo- and heterochiral aggregation during crystallization of organic molecules has significance both for fundamental questions related to the origin of life as well as for the separation of homochiral compounds from their racemates in industrial processes. Herein, we analyse these phenomena at the lowest level of hierarchy - that is the self-assembly of a racemic mixture of (R,R)- and (S,S)-PBI into 1D supramolecular polymers. By a combination of UV/vis and NMR spectroscopy as well as atomic force microscopy, we demonstrate that homochiral aggregation of the racemic mixture leads to the formation of two types of supramolecular conglomerates under kinetic control, while under thermodynamic control heterochiral aggregation is preferred, affording a racemic supramolecular polymer. FT-IR spectroscopy and quantum-chemical calculations reveal unique packing arrangements and hydrogen-bonding patterns within these supramolecular polymers. Time-, concentration- and temperature-dependent UV/vis experiments provide further insights into the kinetic and thermodynamic control of the conglomerate and racemic supramolecular polymer formation. Homo- and heterochiral aggregation is a process of interest to prebiotic and chiral separation chemistry. Here, the authors analyze the self-assembly of a racemic mixture into 1D supramolecular polymers and find homochiral aggregation into conglomerates under kinetic control, while under thermodynamic control a racemic polymer is formed.},
  language  = {en}
}
@phdthesis{Wehner2021,
  author    = {Wehner, Marius},
  title     = {Supramolecular Polymorphism in Homo- and Heterochiral Supramolecular Polymerizations},
  doi       = {10.25972/OPUS-21151},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-211519},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2021},
  abstract  = {The aim of the first part of this thesis was to investigate (R,R)-PBI as a model system for polymorphism at its origin by a supramolecular approach. The pathway complexity of (R,R)-PBI was fine-tuned by experimental parameters such as solvent, temperature and concentration to make several supramolecular polymorphs accessible. Mechanistic and quantum chemical studies on the kinetics and thermodynamics of the supramolecular polymerization of (R,R)-PBI were conducted to shed light on the initial stages of polymorphism. The second part of this work deals with mechanistic investigations on the supramolecular polymerization of the racemic mixture of (R,R)- and (S,S)-PBI with regard to homochiral and heterochiral aggregation leading to conglomerates and a racemic supramolecular polymer, respectively.},
  subject      = {Supramolekulare Chemie},
  language  = {en}
}